1. History of the Technology
Heretofore, artisans in the field of sling technology generally required very large slings formed of a single cable strand of large diameter to provide the capacity to lift heavy loads. Such large slings were heavy and difficult to work with because they were not flexible. Slings of such large proportions also required larger sleeves or collars to maintain them in an assembled configuration. It was generally necessary to employ very large and expensive equipment to form an industrial grade sling when working with such large diameter heavy strand cable.
2. Discussion of the Prior Art
The sling assembly of this invention employs a splice for joining the members of the eye structure to the body structure which is different from the teachings of the prior art which shows the use of the same number of strand components from the eye structure to splice into the body part components. In the instant invention, the tensile strength of the sling assembly is greater than expected because there is less interruption of the load bearing function because less cable strand components form its splice structure. This is described in detail in the summary of the invention.
The prior art concerning sling construction teaches the formation of eye structures first before the body structure, but in this invention, the eyes are formed last. The sling industry has traditionally used only one body strand member out of which the eyes are formed and the body structure is formed by means of a series of double backs and overlaps with a central core member in the body structure. In the present invention, the body structure is formed of three separate body strand members.
The prior art sling structures require larger assemblies to develop the capacity for load lifts which can be achieved by the smaller, lighter, more flexible slings of this invention. Since the prior art required the use of very large slings to lift very heavy loads, it also demanded the use of large expensive sling construction equipment, whereas the slings of this invention can be constructed by hand with little or even no equipment.